The invention relates to an apparatus for sorting and separating discrete articles by shape and size, and particularly to a vibratory apparatus for sorting irregularly-shaped material, such as railroad track material. The railroad track material to be sorted and separated is typically accumulated during dismantlement of abandoned lines of track, and includes fasteners and positioning devices such as tie plates, angle bars, rail anchors, spikes, bolts, and nuts.
Sorting of irregularly-shaped material, such as railroad track material recovered from abandoned lines of track, has typically been accomplished by manual methods of sorting and separating the material. Exclusive of steel rails and wooden ties, each mile of railroad track contains approximately fifty tons of fasteners and positioning devices. Much of this material removed from abandoned lines or railroad track, typically about 85 percent, is physically salvageable for reuse. However, manual methods generally have been too expensive, tedious, time-consuming, and inefficient to justify the expense of sorting and separating track material for reclamation.
Mechanical apparatus have also been used for sorting material, particularly articles which are symmetrical about at least one dimension. For instance, Ettlinger U.S. Pat. Nos. 3,605,767 and 3,738,465 disclose a vibrating sorter for soiled tableware, including a vibrating means for separating plates and silverware. The sorting apparatus of Brumagin U.S. Pat. No. 3,211,289 particularly relates to sorting articles of an elongated shape, such as cucumbers and similarly-shaped vegetables. Lastly, Holman U.S. Pat. No. 3,799,336 relates to a method and apparatus for treating discrete articles, including grading the articles by length.
However, such devices have not successfully solved all of the problems of sorting and separating irregularly-shaped material, such as rail anchors and angle bars included among the track material recovered from abandoned railroad lines. Disadvantages of these devices include an inability to efficiently separate two types of irregularly-shaped articles, and a tendency for these articles to become misaligned, and caught on members for the sorting and separating apparatus, thereby jamming the smooth flow of material through the apparatus.
Furthermore, other apparatus designed for sorting railroad track material have included the combination of a hopper, a feeder positioned at the base of the hopper for regulating the flow of material from the hopper, an oscillating conveyor positioned adjacent the feeder to evenly distribute the material and vibrate foreign matter from the material, and a belt conveyor located at a discharge end of the oscillating conveyor. Sorting and separating of the track material is accomplished in this prior art device manually by persons stationed along both sides of the belt conveyor. Material is placed into appropriate containers depending upon the size and condition of the material. Because this apparatus requires and continues to use a high degree of manual sorting and separating methods, it is relatively unproductive, expensive, tedious, and prone to jamming of material in the hopper.
According to the present invention, an apparatus is provided which overcomes the disadvantages of the prior art in sorting and separating discrete articles by shape and size, particularly irregularly-shaped material such as railroad track material. The apparatus of the invention includes an oscillating conveyor having a trough at a sorting end, a plurality of spaced parallel bars provided at the sorting end of the conveyor, a means for receiving a first group of separated material, and a means for receiving a second group of separated material. The plurality of spaced parallel bars have leading edges extending longitudinally along a trough of the sorting end and projecting beyond an edge of the trough so that a separating zone is defined. The first receiving means is positioned a spaced distance from the leading edge of the bars and receives a first group of material from the top surface of the bars. The second receiving means is positioned beneath the separating zone and receives a second group of smaller-sized material. The second group of smaller-sized material includes a first portion which is conveyed on the trough in the sorting end and separated from the first group by falling over the trough edge in the separating zone. A second portion of the second group of material is conveyed in a potentially jammed position on the bars, and is separated from the first group by falling between the leading edges of the bars and the first group receiving means. This second portion of the second group of material is typically comprised of irregularly-shaped articles.
The apparatus of the invention may include several other components which are advantageously combined to increase productivity and efficiency. These additional components include a hopper, a feeder positioned between a discharge opening of the hopper and a loading end of the oscillating conveyor, a belt conveyor for transporting the first group of material away from the first receiving means, and an elevating conveyor adjacent the belt conveyor. A preferred embodiment of the apparatus includes selected dimensions of the plurality of spaced parallel bars, their distances from one another, a projecting distance of the leading edges of the bars, and the spacing between the leading edges of the bars and the first receiving means. The apparatus of the invention provides many advantages. In comparison with manual sorting methods, productivity is increased over previous sorting apparatus because fewer personnel are needed to supervise operation of the sorting and separating apparatus of this invention, to prevent jams and insure proper orientation of material. The increased productivity decreases the number of worker-hours required to sort the track material, and also increases the overall efficiency of the apparatus, thereby justifying the cost of reclamation of used track material according to the present invention when compared with other methods and apparatus of reclamation in view of the cost of purchasing new material. Moreover, this apparatus produces relatively accurate sorting and separating of material with fewer jams, especially when the material has unusual and various irregular shapes typically found in railroad track material.
Accordingly, it is the primary object of this invention to provide a new and more efficient apparatus for sorting and separating discrete articles, particularly irregularly-shaped material, such as railroad track material.
Another object of this invention is to provide an apparatus of sorting and separating discrete articles, including those of irregular shape, which reduces the number of worker-hours required to sort a given load of material, yet maintains sorting accuracy at a relatively high level.
A further object of this invention is to provide an apparatus which not only sorts and separates irregularly-shaped material but also removes relatively loose foreign matter from the material and allows efficient manual inspection of material for removal of unsalvageable parts.
Other objects, features and advantages of the invention will become apparent upon reading the following detailed description in conjunction with the accompanying drawings.